mac_alias 2.0.0

While it is written in pure Python, some OS X specific code is required to
generate a proper Alias or Bookmark record for a given file, so this module
currently is not portable to other platforms.

Credit is due to Wim Lewis <wiml@hhhh.org>, whose work on reverse engineering
the alias format was extremely useful in writing this code. Alastair Houghton
<alastair@alastairs-place.net> was responsible for reverse engineering the
bookmark format.